


Fated

by Rei_Amakata



Category: Free!
Genre: Alpha/Beta/Omega Dynamics, Bottom Nanase Haruka, Explicit Sexual Content, Fluff and Smut, M/M, Non-Linear Narrative, Porn With Plot, Rinharu Week, Top Matsuoka Rin
Language: English
Status: Completed
Published: 2017-04-27
Updated: 2017-04-27
Packaged: 2018-10-24 12:08:37
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 3,423
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10741416
Author URL: https://archiveofourown.org/users/Rei_Amakata/pseuds/Rei_Amakata
Summary: "Rin Matsuoka, aiming to surpass someone else from his own team? That was a twist.The two of them deciding to become a pair, by impulse, without having their parents know?Well, talk about twist."For RinHaru Week 2017 - Day 4: Competition





	Fated

**Author's Note:**

> For Day 4 I chose the prompt AU: a/b/o. I've been wanting to write an omegaverse AU for a while, but I barely didn't make it to the event. The plot I had (have!) in mind gives way to a long story, one that would have to be split into chapters, I suppose. So I tried to summarize the key points and mix and mingle them with shameless smut. I hope you'll be able to get the idea!  
> Note that the Samezuka Institute isn't canonically depicted; I turned it into an all-sports school owned by the (wealthy) Matsuoka family. As for Haru's parents, I still haven't made up my mind about them being a m/f or a m/m couple.  
> So yes, this one-shot may be just the beginning.

“Are you sure you want this? You know... There’s no turning back if we do it.”

The question was followed by a warm breath that caressed Haruka’s nape, and sent shivers down southern parts of his body. He was aching, trembling, he was feverish. Yes, of course he wanted that, and he wanted Rin to get that done with as soon as possible. He felt like he couldn’t bear it anymore.

It wasn’t just the effects of the heat talking. Ever since he made his mind about no longer being free – and, therefore, subjected to be pretty much everyone’s pray at school – he has wanted it. Badly.

“Just get this over with, Rin. Hurry!” He tried to sound fierce, but the sentence came in a soft whisper.

“And miss all the fun of it? No way, Haru. I’m taking my time.”

As if to show he meant it, the redhead alpha slipped his hand down Haru’s chest, making playful moves around his nipples and bellybutton with the tip of his index. Haruka couldn’t see how his partner was grinning, as he was facing the wall of the office and had Rin behind him, their bodies grinding against each other. He wanted to be rational and worry about what would happen if anyone – Rin’s father, most likely – entered the room, but he just couldn’t. He had been dazed ever since the symptoms started to manifest themselves; his eyes were so clouded as he had walked into the room, barely stumbling, so weak his legs felt then, that he hadn’t even noticed that Rin had locked the door.

He’d been taking the suppressants for quite a while, so much so that he didn’t remember how it felt like to be in that state. The memories came back fast, though, as the heat announced itself. And he could tell then the reactions in his body were finding a mirror in Rin’s; his pink eyes got this somewhat supernatural glimmer. Haru had never seen anything like that before.

Yes, that wasn’t the first time an alpha went into rut thanks to him. But it was the very first an alpha he actually wanted to be a pair with reacted to him.

Rin Matsuoka of all people, huh?

* * *

Haruka Nanase was an omega born to a couple formed by an alpha and a beta. Despite what everybody thought and knew about alphas, his alpha dad wasn’t disappointed when, by age 10, Haru was diagnosed as an omega. Back then, he already showed extreme potential for the sports, and Mr. Nanase knew his son had a place guaranteed in the Samezuka Institute.

However, finding out about his only child status obliged the alpha to take some measures before the plans he had for Haruka could be fulfilled. After all, the Samezuka Institute was known for accepting students based on their social ranks – and while that wasn’t the only criteria considered for the admission, it was one of the most relevant ones.

They took in mostly alphas. And a few betas. And as far as everyone who had connections with the Matsuoka family knew, no omegas.

It wasn’t hard to guess why. Omegas required a different kind of treatment once they reached age 12. Being surrounded by alphas and betas could be quite dangerous for them. In addition to that was the fact that they were the weakest in that society; which meant they certainly wouldn’t be as skilled and prepared for sports and the like as an alpha, or even a beta would. Moreover, at least as professionals, they would require the use of suppressants not to let their condition get in the way of eventual matches and tournaments. Plus, the use of that kind of medicine may lead them to be accused of doping and, at some point, harm their neurological health. It was a high risk to take, and one most sports school weren’t willing to. That was particularly true for the renowned Samezuka Institute, which was by far the best in the field in Japan.

In spite of all that, Mr. Nanase didn’t give up. He knew his son was different and worth any risks. As long as they took the proper cautions, he should be fine. And, eventually, thanks to his own connections as a high-ranked alpha, he would find a partner that would suit Haruka and make sure that person and his boy became a pair. Once that happened, there would be no limits for the young omega’s success.

Of course, having Haruka become a pair with none other than the son of the Samezuka Institute’s president hadn’t been part of his plans.

* * *

Rin trailed his tongue over the spot on Haru’s neck that was supposed to receive his mark later on. He was having too much fun! When he and Haru met, he doubted the silent, blank faced Nanase guy would be a challenge of any kind to him. As the captain of the swimming team in the institute – and an heir of the Matsuoka empire – he’d been prepared to stand at the top for a long while. Even great swimmers from important families as his own didn’t even get close to him. He was the admired _senpai_ of the team, although he believed that in certain modalities team work was more important than individual effort. It didn’t matter if you were the best, if you were part of a team and there wasn’t agreement on the amount of energy all of you should put into that, it was useless.

Rin believed swimming with a team was way more fun than just getting medals by himself, so despite being notorious for his individual performance, he would always inject a dose of team spirit in his fellow swimmers.

The oldest Matsuoka had also learned the concept of rivalry early in life, but it proved to be way different than the theories and juvenile experience he’d had when Haru joined the institute.

The silent boy who appeared to offer no challenge ended up being the very competitor that kept him wide awake at night – which in time started to happen for all kinds of reasons but not only because Rin wanted to surpass him.

He, Rin Matsuoka, aiming to surpass someone else from his own team? That was a twist.

The two of them deciding to become a pair, by impulse, without having their parents know? Well, talk about twist.

* * *

Haru felt his cock ache as it was tightened by his swimming suit. He was wearing the school’s uniform over that – well, by then he only had the pants on – and they felt heavy, warm and as though they were glued to his body.

“I need to... Take this out,” he muttered.

As he slipped his hands up and down Haru’s body, not risking to skip any inch of it, Rin noticed how feverish the blue-eyed boy felt. His skin was probably just as warm, for he felt like he was burning inside. Haru’s scent was driving him crazy; he also felt a tightness down his crotch. So yes, maybe they needed to be released from those inconvenient garments. He turned the omega around and almost gasped as he saw the blush on his face and the clouded, aroused look the boy had on.

“Let’s... Take these off,” he mumbled, finding it hard to keep his self-control.

Haru just nodded, and the two of them proceeded to remove the remaining pieces of clothes. The omega, being in a more difficult situation, couldn’t keep himself from moaning as he fought against the spandex swimsuit.

“You should consider wearing actual underwear every now and then, you know?” Rin commented as he had freed himself from his own clothes and stared at Haru.

“I do. Every now and then.”

As he said so, the blue-eyed boy tossed the piece of clothing aside and raised his head, gazing at the redhead. Rin was instantly mesmerized. He felt something similar to what he had felt the first time he saw Haru swim. He had been speechless, stunned and completely taken aback.

“Who’s this guy?” Had been his first thought, back then. He had almost flown from the aquatic gymnasium straight to his dad’s office to ask details about that kid. Not that Mr. Matsuoka would release any information; he kept students’ data private as the rules determined. They wouldn’t even know the ranks of one another unless they announced so themselves. Alphas, proud as they were, usually would blurt it out at any chance they got. Betas would rather avoid the subject, but wouldn’t deny once they were found out.

Omegas like Haru would give everything to keep that buried. But he particularly didn’t care; he just did as he was told to avoid unpleasant situations. He knew omegas were despised by many people and that that could get him in trouble, so he let them believe he was an alpha instead.

Rin had found out the truth about him by chance, and in an awkward situation, since it happened on an occasion where Haru had forgotten to bring his medicine to school. It happened to be one of his heat periods, and it hadn’t been pleasant to try and escape from school under those impairing conditions. The redhead had pretended, unconvincingly though, not to notice what was going on. It had been pretty hard, for as soon as he saw Haru in that state, he started to feel weird himself.

Since then, he’d eventually catch himself off guard by thoughts about how it would be like if he and Haru could be a pair. He’d mentally scold himself for that, but find the thought popping up on his mind again no long after.

And then, sooner than he’d hoped for, there they were.

“You should see yourself, Haru. It’s such a sight,” Rin smirked, feeling bold enough to make that remark, but not sufficient to keep himself from blushing as he did.

“Instead of staring, you should be doing something,” came the muffled retort.

The alpha loved how his pair-to-be didn’t hold back. He was too defiant for an omega, and that was amusing. Also, that was probably the very reason why Rin couldn’t refrain; his heart was beating like mad inside his chest. He threw another look over Haru, taking in every detail of the boy in front of him. Just then, he was startled as a groan escaped Haru’s lips. He was reaching his limit, and they weren’t even touching.

As it turns out, Haru was also observing the bare alpha who stood there. But that didn’t last long, as he soon pulled Rin close and glued their lips together.

As the gap between their bodies was closed, the both of them let out a soft moan. They were aroused to a point that was nearly painful, and Rin no longer wanted to take his time. Haru’s urgency matched his; the omega couldn’t keep even a shade of the straight-face he’d been able to sustain – even if hardly – until then.

Feeling a warm wetness on his thigh, Rin hurried his hand and grabbed Haru’s cock, not wasting a second more to start pumping it.

To witness the omega with his eyes closed and breathing hard as they went was something Rin swore he’d always be thankful for.

* * *

“Are you... Sure? This is a big deal, Haru.”

“What, you don’t want it? If you don’t, well... We can still do _that_ , I’ll take the contraceptive anyway and end of story.”

The redhead had averted his gaze from the wilful boy. How come Haru was able to talk about stuff like that like it was nothing much?

“No, I don’t want us to be a... One-night stand, I guess. I respect you.”

Haru had laughed, something he rarely did. In front of Rin, anyway.

“Now you make it sound like I’m a girl. We’re men, Rin.”

“I know that!”

“So... Are you in?” The omega insisted.

“I’ll let you know when things are set. But, Haru... Don’t make it sound as though this is a contract or something.”

“It kind of works that way, Rin.”

Rin had fought his fluster to look Haru in the eye as he said, “A contract doesn’t necessarily requires love. This does.”

He had kissed the omega before he could counter that.

* * *

“Don’t tell me he’s fast even at that!” Rin thought, stunned by the moist sensation in his hand. Haru’s cum had splattered over both their bellies and on his palm.

However, he knew he wouldn’t be able to hold up his for much time himself. He felt the throbbing below and he could tell Haru wasn’t ignorant of that either.

“Hurry, Rin. I’m... Ready for it.”

He blinked, still stunned by Haru’s bluntness. That guy was really something!

Aware as he was of his condition, he didn’t hold up and instead, turned Haru on his back again, face to the wall, as his own hands sought for the inviting entrance. As he inserted one, then two fingers, which slipped into effortlessly, he realized that Haru meant what he had said.

He was literally _ready_.

* * *

The first time Haruka heard somebody talk about being a pair – and not only that, but about how things worked in their society – it had been from his grandma. She was an omega as well, and back in her days things used to be way tougher for people like them.

“The best chance we had would be to find an alpha that would protect us, Haru-chan,” she had told him.

The young boy had gazed at his grandmother. He didn’t get it. Why must they depend on people just because of their rank? He didn’t think his grandma was weak at all. She took good care of him and protected him from a lot of stuff herself.

“I know it sounds strange, but it’s just how things were. And then female omegas like me would dream about finding an alpha that would not only protect us, but be our fated match.”

That sounded even more confusing to Haru. “Fated match?”

“Yes. It means they’re the person an omega will become a pair with and then, no one else will ever be able to touch them, that is, until the alpha passes away.”

“It should feel awful to be trapped in someone like that,” Haruka had thought to himself.

“Well, when you grow up, Haru-chan... Either you’re found to be an alpha or a beta, I hope you’ll meet your fated one,” she had said, her voice filled with warmth.

“I guess I won’t want it, grannie,” he’d replied, and that had amused her.

How wrong had he been!

* * *

Three fingers were moving in rhythmic moves, dancing easily inside the wet cavity. While Rin aimed at Haru’s most sensitive spot, he was getting ready to rehearse a bite, his lips touching the raven-haired boy’s shoulder. Each thrust against his prostate sent a rush of blood down Haruka’s lower parts. To Rin’s amazement, soon he was sporting an erection again. When that happened, Haru made a move to try and relieve it himself. The redhead was quicker, though, and stopped him in time.

“Nope. Let me handle that for you,” he said in a low voice that surprised the omega.

In no time Rin’s hand was circling his partner’s dick once again, and he went on taking care of both sides without neglecting any. Quite to the contrary; while his hands diligently caressed the lower parts, his mouth dedicated the same amount of attention to Haruka’s bare shoulder.

A soft bite pressed on the upper part and made the omega jolt, moving his hip against Rin by mere reflex. That made the alpha release a low moan.

Things were intensifying, and as the vigorous pump to his front made Haru once again reach unbearable levels of pleasure, the reflexive moves of his hip became more frequent and urgent. Rin couldn’t take it.

Hurriedly, he removed the fingers and used the same hand to grab Haru’s ass.

“Ha-ru... I’m putting it in,” he murmured close to the boy’s ear, the hot air from his breath brushing the omega’s skin lightly.

Haru just nodded and raised his hip again, in an almost imperceptible motion.

The waves of pleasant sensations that followed engulfed the both of them. Every thrust reflected on a tighter grip on Haru’s erection. He had to bring the back of his wrist to his mouth to muffle the unstoppable groans. Soon, a few drops of semen were spouting on the head of his cock.

“Fast, Rin... Do it!” He commanded, and closed his eyes as he felt the alpha’s mouth on his nape, planting a wet kiss there as though to prepare it to be invaded as well.

With all that happening in such a deep and fast way, Haru was losing every drop of reason he’d ever had, and not regretting it one bit.

* * *

The moment Haruka started to consider Rin as a potential pair had been the same as for his teammate.

It was the day when he forgot his suppressant at home, and was unlucky enough to have it be the day he was supposed to go into heat period.

When the first signs displayed themselves, he rushed to the restroom. He knew he had to hide and try and take care of the situation by himself as soon as possible.

A student from the soccer wing had been there, which almost caused Haru to go through a dreadful event.

Luckily, though, Rin had entered the room just as the strong player was punching the door of the toilet stall he was hiding in.

“Yo, what’s the matter?”

The student had dashed out of the restroom, leaving a confused and suspicious Matsuoka behind. He knew people were afraid of being caught in the middle of attempting to break any of the institute’s strict rules. He was a Matsuoka, after all.

“Hey, is there anyone here?”

He’d asked, stepping close to the locked door.

When Haru left the toilet, flushed and trembling, Rin had stared at him in shock.

“Haru!?”

And Haru knew being close to an alpha under those circumstances was dangerous. But he hadn’t been prepared to behold the ethereal gleam in Rin’s eyes.

Also, he hadn’t been ready to the twirling in his stomach that sight caused him just before he ran away.

Ever since that day, he would have a recurrent dream where he was bitten by Rin.

* * *

The burning pain on his neck made Haru bite his lower lip so that he wouldn’t gasp nor scream. He bit it hard enough to almost taste his own blood.

He had come just a second ago, and was now feeling Rin’s spasms as the redhead came as well, inside of him, at the same time he turned Haruka into his pair.

Rin’s pointy teeth proved to be real sharp as they pierced Haru’s skin. The sensation that grip brought to the alpha was beyond explanation. He felt a rush taking over his body, and he couldn’t really tell if the orgasm had anything to do with that. All he knew was that he wanted to become one with that omega, he felt close to being fused into one with the guy he was entangled with. His arms were firmly wrapped around Haru’s chest, pulling his torso against himself. He pressed his mouth against the recent marked spot, licking the blood off it as soon as his teeth let go of that skin.

He was still trembling and feeling the thick liquid that pasted to his legs warming his thighs.

He’d never felt anything of the sort before.

“Haru…” he called in a faint voice. “This was wonderful… It’s the best thing I’ve ever done in my entire life.”

“You’re only seventeen,” the omega replied, and while those words seemed to form a dry response, his tone was warm.

“Well, that’s good, isn’t it? It means that a long future awaits. I’ll have a long time to spend with you, _Nanase_.”

Silent, Haru turned around and faced Rin. He was finally getting back to a normal state, still, there was a different kind of glint in his blue eyes.

“You better do, Rin.”

The alpha just threw his arms around him, holding him tight. And he held his alpha back. _His_ alpha.

That guy was now his pair.

His fated match. For a lifetime.

He was now trapped forever in someone, just like that.

Rin Matsuoka of all people, huh?

And, damn, it felt right.

**Author's Note:**

> I'm a sucker for fluffs and well, endings aren't my specialty, but I hope this one was ok. I tried to make it a little bit fluff to balance the lewd content. haha  
> Thanks for reading it!


End file.
